scholarly journals In Vivo Evaluation of Novel Geranylgeranyl Diphosphate Synthase Inhibitors

Blood ◽  
2018 ◽  
Vol 132 (Supplement 1) ◽  
pp. 215-215 ◽  
Author(s):  
Staci L. Haney ◽  
Yashpal S. Chhonker ◽  
Michelle L. Varney ◽  
Geoffrey A. Talmon ◽  
Daryl J. Murry ◽  
...  

Abstract The enzyme geranylgeranyl diphosphate synthase (GGDPS) synthesizes the 20-carbon isoprenoid geranylgeranyl diphosphate which is used in protein geranylgeranylation reactions. Our work has demonstrated that GGDPS inhibitors (GGDPSIs) represent a novel therapeutic strategy for multiple myeloma (MM) by disrupting Rab protein geranylgeranylation. Treatment of MM cells with GGDPSI results in disruption of monoclonal protein trafficking, leading to induction of the unfolded protein response pathway (UPR) and apoptosis. We have previously reported preclinical studies with a lead GGDPSI, VSW1198 (a mixture of homogeranyl/homoneryl triazole bisphosphonates), demonstrating the agent's metabolic stability, prolonged half-life (plasma elimination half-life of 47.7 (±7.4) hrs), systemic distribution and confirmed in vivo disruption of geranylgeranylation (Haney et al., Invest New Drugs, 2018). Additional structure-function efforts have led to the development of the α-methylated derivatives RAM2093 (homogeranyl) and RAM2061 (homoneryl). Intriguingly the addition of the α-methyl group abrogates the effects of the olefin stereochemistry on inhibitor potency such that the individual isomers display near identical ability to disrupt protein geranylgeranylation in enzyme and cell assays (Matthiesen et al., Bioorg Med Chem, 2018). As little is known regarding the impact of olefin stereochemistry on the pharmacokinetic (PK)/pharmacodynamic (PD) properties of drugs, we pursued additional in vitro and in vivo studies of RAM2093 and RAM2061 and investigated the efficacy of the GGDPSIs in a mouse MM xenograft model. In MM cell lines, qRT-PCR and western blot analysis showed that both isomers induce activation of UPR/apoptotic markers in a dose-dependent manner and with similar potency. Single dose testing in CD-1 mice identified a maximum tolerated dose of 0.5 mg/kg IV for RAM2061 and 0.3 mg/kg for RAM2093. Liver toxicity was the primary barrier to dose escalation with both compounds. Analysis of blood samples showed elevated liver transaminase levels with normal bilirubin/alkaline phosphatase levels and histopathological examination confirmed evidence of hepatocyte injury at higher doses. Multi-dose schedules of 0.1 mg/kg twice a week (two weeks on, one week off, two weeks on) for RAM2061 and RAM2093, as well as 0.2 mg/kg (RAM2061) and 0.15 mg/kg (RAM2093) weekly x four weeks were tested. All dosing schedules were tolerated with the exception of the twice-weekly schedule for RAM2093. Consistent with the findings from our single dose testing, both multi-dose schedules induced transient elevation of hepatic transaminases. No loss of weight was observed and creatinine and CBC results were within normal limits for both single and multi-dose injected animals. Importantly, western blot analysis of mouse tissues collected from both RAM2061 and RAM2093 multi-dose-treated mice showed accumulation of unmodified Rap1a in the liver, kidney and spleen, indicating in vivo disruption of protein geranylgeranylation was achieved. Furthermore, using MM.1S MM cell flank xenographs in NOD-SCID mice, we observed a significant reduction in tumor growth in mice treated with either VSW1198 or RAM2061 relative to vehicle control. Lastly, PK/biodistribution studies with RAM2093 and RAM2061 were performed following a single dose of 0.3 mg/kg IV. Both compounds were detectable in plasma and liver samples for up to seven days post-injection demonstrating prolonged half-life and tissue distribution. The full PK parameters for both compounds will be presented and studies measuring drug levels in other tissues are ongoing. Taken together, these data suggest that RAM2061 and RAM2093 have equivalent anti-MM activity in vitro, but that RAM2061 is better tolerated in vivo. Whether this is a consequence of different PK properties vs. differences in tissue uptake or metabolism will be determined. These studies also confirm the in vivo efficacy of our novel GGDPSIs and support further development of these agents for the treatment of MM. Figure. Figure. Disclosures Holstein: Celgene: Consultancy, Membership on an entity's Board of Directors or advisory committees.

2010 ◽  
Vol 113 (Special_Supplement) ◽  
pp. 228-235 ◽  
Author(s):  
Qiang Jia ◽  
Yanhe Li ◽  
Desheng Xu ◽  
Zhenjiang Li ◽  
Zhiyuan Zhang ◽  
...  

Object The authors sought to evaluate modification of the radiation response of C6 glioma cells in vitro and in vivo by inhibiting the expression of Ku70. To do so they investigated the effect of gene transfer involving a recombinant replication-defective adenovirus containing Ku70 short hairpin RNA (Ad-Ku70shRNA) combined with Gamma Knife treatment (GKT). Methods First, Ad-Ku70shRNA was transfected into C6 glioma cells and the expression of Ku70 was measured using Western blot analysis. In vitro, phenotypical changes in C6 cells, including proliferation, cell cycle modification, invasion ability, and apoptosis were evaluated using the MTT (3′(4,5-dimethylthiazol-2-yl)2,5-diphenyltetrazolium bromide) assay, Western blot analysis, and cell flow cytometry. In vivo, parental C6 cells transfected with Ad-Ku70shRNA were implanted stereotactically into the right caudate nucleus in Sprague-Dawley rats. After GKS, apoptosis was analyzed using the TUNEL (terminal deoxynucleotidyl transferase–mediated deoxyuridine triphosphate nick-end labeling) method. The inhibitory effects on growth and invasion that were induced by expression of proliferating cell nuclear antigen and matrix metalloproteinase–9 were determined using immunohistochemical analyses. Results The expression of Ku70 was clearly inhibited in C6 cells after transfection with Ad-Ku70shRNA. In vitro following transfection, the C6 cells showed improved responses to GKT, including suppression of proliferation and invasion as well as an increased apoptosis index. In vivo following transfection of Ad-Ku70shRNA, the therapeutic efficacy of GKT in rats with C6 gliomas was greatly enhanced and survival times in these animals were prolonged. Conclusions Our data support the potential for downregulation of Ku70 expression in enhancing the radiosensitivity of gliomas. The findings of our study indicate that targeted gene therapy–mediated inactivation of Ku70 may represent a promising strategy in improving the radioresponsiveness of gliomas to GKT.


2020 ◽  
Author(s):  
Tao Yan ◽  
Xin Chen ◽  
Hua Zhan ◽  
Penglei Yao ◽  
Ning Wang ◽  
...  

Abstract BackgroundThe tumor microenvironment plays an important role in tumor progression. Hyaluronic acid (HA), an important component of the extracellular matrix in the tumor microenvironment, abnormally accumulates in a variety of tumors. Whereas the role of abnormal HA metabolism in glioma remains unclear. MethodsThe expression level of hyaluronic acid (HA) was analyzed by ELISA assay and proteins such as HAS3, CD44, P62, LC3, CCND1 and CCNB1 were measured with Western blot analysis. The cell viability and proliferation were measured by MTT and KI67 immunofluorescence staining respectively. Autophagic vesicles and autophagosomes were quantified by transmission electron microscopy (TEM) and GFP-RFP-LC3 fluorescence analysis respectively. Cell cycle was analyzed by flowcytometry and Western blot analysis. Immunohistochemical (IHC) staining was used to detect expression levels of HA, Ki67, HAS3 and CD44 in human and mouse tumor tissues. Lentivirus constructed HAS3 and CD44 knockout stable glioma cells were transplanted to BALB/C nude mice for in vivo experiments. 4-Methylumbelliferone (4MU) was also used to treat glioma bearing mice for verifing its anti-tumor ability. The expression curve of HAS3, CD44 and the disease-free survival (DFS) curves for HAS3, CD44 in patients with LGG and GBM was performed based on TCGA database. ResultsAs shown in the present study, HA, hyaluronic acid synthase 3 (HAS3) and a receptor of HA named CD44 are expressed at high levels in human glioma tissues and negatively correlated with the prognosis of patients with glioma. Silencing HAS3 or blocking CD44 inhibited the proliferation of glioma cells in vitro and in vivo. The underlying mechanism was attributed to the inhibition of autophagy flux and further maintaining glioma cell cycle arrest in G1 phase. More importantly, 4-Methylumbelliferone (4-MU), a small competitive inhibitor of UDP with the ability to penetrate the blood-brain barrier (BBB), also inhibited the proliferation of glioma cells in vitro and in vivo. ConclusionApproaches that interfere with HA metabolism by altering the expression of HAS3 and CD44 and the administration of 4-MU potentially represent effective strategies for glioma treatment.


Author(s):  
Storm N. S. Reid ◽  
Joung-Hyun Park ◽  
Yunsook Kim ◽  
Yi Sub Kwak ◽  
Byeong Hwan Jeon

Exogenous lactate administration has more recently been investigated for its various prophylactic effects. Lactate derived from potential functional foods, such as fermented oyster extract (FO), may emerge as a practical and effective method of consuming exogenous lactate. The current study endeavored to ascertain whether the lactate derived from FO may act on muscle cell biology, and to what extent this may translate into physical fitness improvements. We examined the effects of FO in vitro and in vivo, on mouse C2C12 cells and exercise performance indicators in mice, respectively. In vitro, biochemical analysis was carried out to determine the effects of FO on lactate content and muscle cell energy metabolism, including adenosine triphosphate (ATP) activity. Western blot analysis was also utilized to measure the protein expression of total adenosine monophosphate-activated protein kinase (AMPK), p-AMPK (Thr172), lactate dehydrogenase (LDH), succinate dehydrogenase (SDHA) and peroxisome proliferator-activated receptor gamma coactivator-1α (PGC-1α) in response to FO administration. Three experimental groups were formed: a positive control (PC) treated with 1% horse serum, FO10 treated with 10 μg/mL and FO50 treated with 50 μg/mL. In vivo, the effects of FO supplementation on exercise endurance were measured using the Rota-rod test, and Western blot analysis measured myosin heavy-chain 2 (MYH2) to assess skeletal muscle growth, alongside p-AMPK, total-AMPK, PGC-1α, cytochrome C and UCP3 protein expression. Biochemical analysis was also performed on muscle tissue to measure the changes in concentration of liver lactate, lactate dehydrogenase (LDH), glycogen and citrate. Five groups (n = 10/per group) consisted of a control group (CON), exercise group (Ex), positive control treated with Ex and 500 mg/kg Taurine (Ex-Tau), Ex and 100 mg/kg FO supplementation (Ex-FO100) and Ex and 200 mg/kg FO supplementation (Ex-FO200) orally administered over the 4-week experimental period.FO50 significantly increased PGC-1α expression (p < 0.001), whereas both FO10 and FO50 increased the expression of p-AMPK (p < 0.001), in C2C12 muscle cells, showing increased signaling important for mitochondrial metabolism and biogenesis. Muscle lactate levels were also significantly increased following FO10 (p < 0.05) and FO50 (p < 0.001). In vivo, muscle protein expression of p-AMPK (p < 0.05) and PGC-1α were increased, corroborating our in vitro results. Cytochrome C also significantly increased following FO200 intake. These results suggest that the effects of FO supplementation may manifest in a dose-response manner. FO administration, in vitro, and supplementation, in vivo, both demonstrate a potential for improvements in mitochondrial metabolism and biogenesis, and even for potentiating the adaptive effects of endurance exercise. Mechanistically, lactate may be an important molecule in explaining the aforementioned positive effects of FO.


2009 ◽  
Vol 296 (3) ◽  
pp. G499-G509 ◽  
Author(s):  
Mallikarjuna R. Metukuri ◽  
Donna Beer-Stolz ◽  
Rajaie A. Namas ◽  
Rajeev Dhupar ◽  
Andres Torres ◽  
...  

We have previously demonstrated that the Bcl-2/adenovirus EIB 19-kDa interacting protein 3 (BNIP3), a cell death-related member of the Bcl-2 family, is upregulated in vitro and in vivo in both experimental and clinical settings of redox stress and that nitric oxide (NO) downregulates its expression. In this study we sought to examine the expression and localization of BNIP3 in murine hepatocytes and in a murine model of hemorrhagic shock (HS) and ischemia-reperfusion (I/R). Freshly isolated mouse hepatocytes were exposed to 1% hypoxia for 6 h followed by reoxygenation for 18 h, and protein was isolated for Western blot analysis. Hepatocytes grown on coverslips were fixed for localization studies. Similarly, livers from surgically cannulated C57Bl/6 mice and from mice cannulated and subjected to 1–4 h of HS were processed for protein isolation and Western blot analysis. In hepatocytes, BNIP3 was expressed constitutively but was upregulated under hypoxic conditions, and this upregulation was countered by treatment with a NO donor. Surprisingly, BNIP3 was localized in the nucleus of normoxic hepatocytes, in the cytoplasm following hypoxia, and again in the nucleus following reoxygenation. Upregulation of BNIP3 partially required p38 MAPK activation. BNIP3 contributed to hypoxic injury in hepatocytes, since this injury was diminished by knockdown of BNIP3 mRNA. Hepatic BNIP3 was also upregulated in two different models of liver stress in vivo, suggesting that a multitude of inflammatory stresses can lead to the modulation of BNIP3. In turn, the upregulation of BNIP3 appears to be one mechanism of hepatocyte cell death and liver damage in these settings.


Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 126-126 ◽  
Author(s):  
Weirui Zhang ◽  
David Motto ◽  
David Ginsburg

Abstract Thrombotic thrombocytopenic purpura (TTP) is a life threatening illness due to a deficiency of the VWF-cleaving protease, ADAMTS13. The ADAMTS13 protein is composed of a propeptide, followed by a typical zinc metalloprotease domain. The C-terminal 2/3 of the molecule contains disintegrin-like, cystine-rich, and spacer domains, as well as a total of eight TSP1 motifs and two CUB domains. The function of this C-terminal portion of the molecule and its composite motifs is unknown, though TSP1 and CUB domains of other proteins have been shown to mediate protein-protein interactions. To further explore the interaction between ADAMTS13 and VWF, we cloned full length human cDNAs for both ADAMTS13 and VWF into the mammalian expression vector pcDNA3.1. These constructs were transiently transfected into 293T cells and COS cells respectively, and conditioned media collected for analysis. Using an anti-myc antibody, myc-tagged VWF co-immunoprecipitated (co-IP) with ADAMTS13, as demonstrated by western blot analysis using antisera raised against a C-terminal peptide derived from the predicted ADAMTS13 sequence. This direct interaction required partial denaturation of VWF in 1M urea, with no co-IP observed in the absence of urea. To map the segment within ADAMTS13 responsible for VWF binding, we cloned a series of overlapping ADAMTS13 fragments into the bacterial expression vector, Pet44b. Fusion proteins were purified by binding of the included His-tag to Ni-NTA beads and incubated with recombinant myc-VWF in the presence of 1M urea. Association with VWF was analyzed by co-IP with anti-myc followed by western blot analysis using an antibody to the C-terminal HSV-tag present in each fusion protein. The CUB2 (Glu1298- Thr1427) fusion protein co-IP’d with full-length VWF and also demonstrated concentration-dependent competition with full-length ADAMTS13 for VWF binding. In summary, we have demonstrated a direct protein-protein interaction between VWF and ADAMTS13. Binding requires partial denaturation of VWF and appears to be mediated primarily through contacts with the ADAMTS13 CUB2 domain. This interaction may account for the previously observed co-purification of VWF and ADAMTS13 from human plasma. Furthermore, the requirement for 1M urea suggests that this interaction may only occur physiologically under conditions of high shear. Though others have shown that the C-terminal domains of ADAMTS13, including CUB2, are not required for VWF cleavage in vitro, our data, together with several C-terminal mutations previously reported in TTP patients, suggest that interactions between VWF and the ADAMTS13 CUB2 domain may be important in vivo.


2013 ◽  
Vol 31 (4_suppl) ◽  
pp. 190-190
Author(s):  
James M. Lindberg ◽  
Sara J Adair ◽  
Timothy E. Newhook ◽  
Alison Kim ◽  
J Thomas Parsons ◽  
...  

190 Background: Aberrant MAPK and EGFR family signaling are key drivers of pancreatic ductal adenocarcinoma(PDAC). We hypothesized that combination trametinib(MEK1/2 inhibitor), panitumumab(EGFR inhibitor) and trastuzumab(Her2 inhibitor) would more effectively suppress tumor growth than any of these monotherapies. Methods: Patient-derived PDAC cell line MAD09-366 was exposed to trametinib, panitumumab, trastuzumab, and combination therapies in vitro. Western blot analysis was performed on treated cell lysates. Athymic, nude mice were orthotopically implanted with patient-derived PDAC xenografts(MAD09-366, 08-608, and 08-738). Established murine tumors were treated with control, trametinib (0.3mg/kg, qDay), panitumumab (500ug, BIW), trastuzumab (200ug, BIW) or in combination. MRI was used to assess tumor response. Results: Two of 3 PDACs were Kras mutant, 2 of 3 demonstrated increased Her2 activity, and all 3 showed increased EGFR activity. In vitro studies showed increased growth inhibition of triple-therapy-treated cells relative to control or each inhibitor alone. Western blot analysis revealed that EGF stimulation increased Ras pathway signaling in this Kras-mutant cell line. With EGF stimulation, the greatest Ras pathway signaling inhibition was seen in triple-therapy-treated cells. In vivo studies in all PDAC xenografts revealed that triple therapy significantly decreased tumor growth rate relative to control, trametinib alone, panitumumab alone, or panitumumab plus trastuzumab. In 2 of 3 PDACs assessed, triple therapy was superior to trametinib plus panitumumab. Average tumor size in MAD08-738 triple-therapy-treated mice decreased by 9.3%. Conclusions: Triple therapy with trametinib, panitumumab, and trastuzumab demonstrated the greatest in vitro Ras signaling blockade. In vivo, this combination produced significant tumor growth inhibition or regression in all PDAC tumors studied. This regimen should be considered for a future clinical trial in pancreatic cancer patients.


Blood ◽  
2013 ◽  
Vol 122 (21) ◽  
pp. 1658-1658
Author(s):  
Stefano Buttiglieri ◽  
Carmelo Carlo-Stella ◽  
Tiziana Spatola ◽  
Roberta Pulito ◽  
Luigi Naldini ◽  
...  

Abstract Introduction TNF-related apoptosis-inducing ligand (TRAIL) is a protein functioning as a ligand that induces the process of cell death. TRAIL has been shown to kill in vitro a wide variety of tumor cells with minimal effects on normal cells. Despite its in vitro activity, recombinant soluble TRAIL has so far shown limited efficacy in vivo. In contrast, recent reports have shown that significant apoptosis can be observed both in vitro and in vivo when TRAIL is expressed on the cell membrane (mTRAIL). A further innovation might be the delivery of bioactive proapoptotic TRAIL through its expression by extracellular vescicles (EVs), the nanovesicular organelles secreted by cells. In fact, EVs are viewed as an effective tool for intercellular cross-talk and receptor discharge. The trans-membrane expression of TRAIL ligand within the double layer exosomal membrane may induce a more potent death signal when compared with the soluble molecule. Material and Methods Mesenchymal Stromal Cells (MSC) from bone marrow were cultured in vitro and used for EVs production. Cultured MSC in 75 cm2 flasks, at 80% confluence were infected with a lentivector encoding TRAIL, maintained in culture, and cell-supernatants repeatedly collected over several days, ultracentrifugated, with EVs-containing pellet harvested in PBS. EVs were produced also from uninfected MSC as control (EVs-CTRL). EVs were characterized by flow cytometry for expression of MSC markers and mTRAIL, EV size was evaluated by NanoSight technology. Total protein concentration was used to quantify EVs, Western Blot analysis was performed to characterize membrane-bound TRAIL. In vitro analysis was performed on SU-DHL-4 (human B cell lymphoma) and MEL-1300 (human melanoma) cell lines, exposed for 24 hours to 20-100 μg/ml EVs-TRAIL or EVs-CTRL. Annexin/propidium iodide assay was used to quantify apoptotic/necrotic cells. For the in vivo assessments, SU-DHL-4 and MEL-1300 cells were transduced with Luc-Lentiviral particles to obtain Luciferase positive cell lines. These cells were used to engraft NOD scid gamma (NSG) mice (2x106 SU-DHL-4 and 3x105 MEL-1300 cells for each subcutaneous injection point). To visualize tumor cells, mice were injected intraperitoneum with luciferin and analyzed with the Xenogen system. Mice bearing subcutaneous tumor nodules received single intravenous injections of 100, 200, 300 µg or multiple (x 3) 200 µg injections of either EVs-TRAIL or EVs-CTRL. Results FACS analysis showed strong TRAIL expression on EVs from TRAIL-infected MSC compared to EVs-CTRL, with a high proportion of positive particles (median 85%, range 78-93). In addition, EVs-TRAIL displayed MSC membrane markers, i.e. CD 105, CD 90, CD73 and CXCR4. Western Blot analysis under non-reducing conditions showed the presence of TRAIL ligand, with strong prevalence of dimeric TRAIL isoform (barely detectable the trimeric isoform, undetectable monomeric isoforms). NanoSight analysis revealed that EVs had a variable size, up to approximately 400 nm in diameter, with a predominant peak at 273 nm. A strong and dose-dependent cytotoxic effect was observed on SU-DHL-4 cells exposed to EVs-TRAIL (annexin/PI+ve cells: up to 87% for 100 μg/ml EVs-TRAIL), compared to EVs-CTRL exposure (15% Annexin/PI+ve cells for 100 μg/ml EVs-TRAIL). A similar, albeit less pronounced in vitro cytotoxic effect of EVs-TRAIL was observed on the melanoma MEL-1300 cell line. The anti-tumor effect was remarkably strong when EVs-TRAIL were injected in vivo in mice bearing either SU-DHL-4 or MEL-1300 nodules. A marked reduction of the tumor luminescence from 1.2x1010 photon/sec to <108 photon/sec was observed at seven days since a single EVs-TRAIL injection at 200 and 300 μg. Multiple administrations of 200 μg EVs-TRAIL induced the strongest luminescence reduction, as observed in MEL-1300 bearing NSG mice. Histological examination of nodules from EVs treated mice showed necrosis areas along with extensive intra-tumor vascular disruption. Conclusion EVs isolated from genetically engineered TRAIL-expressing MSC: i. do express mTRAIL; ii. display potent antitumor activity, inducing extensive apoptosis/necrosis both in vitro and in vivo in animal models bearing lymphoma and melanoma nodules. Thus, EVs-TRAIL may represent a promising strategy for delivering pro-apoptotic signals to tumor cells. Moreover, the Results could pave the way to the use of EVs for therapeutic purposes. Disclosures: No relevant conflicts of interest to declare.


2011 ◽  
Vol 2011 ◽  
pp. 1-10 ◽  
Author(s):  
Abhinav Sidana ◽  
Muwen Wang ◽  
Wasim H. Chowdhury ◽  
Antoun Toubaji ◽  
Shabana Shabbeer ◽  
...  

Valproic Acid (VPA) is a histone deacetylase inhibitor that holds promise for cancer therapy. Here, we investigate whether VPA treatment induces neuroendocrine differentiation of Prostate Cancer (PCa). A tissue microarray of VPA-treated and untreated tumor xenografts and cell lines of human PCa (LNCaP, C4-2, DU145, and PC-3) were generated and were analyzed by immunohistochemical analysis (IHC) for NE markers chromogranin A (CgA), synaptophysin, and NCAM (neural cell adhesion molecule). Western blot analysis for CgA was performed to confirm the results of the TMA. IHC analysis did not reveal any induction of CgA, synaptophysin, or NCAM in any xenograft after VPA treatmentin vivo.In vitro, VPA treatment induced little synaptophysin expression in C4-2 and PC-3 cells and NCAM expression in LNCaP and PC-3 cells. In the case of CgA, VPA treatment decreased its expressionin vitroin a dose-dependent manner, as determined by western blot analysis. Thus our data demonstrates that VPA does not induce NE differentiation of PCa cells in the physiologically relevantin vivosetting.


2020 ◽  
Vol 52 (4) ◽  
pp. 345-362 ◽  
Author(s):  
Xiaodong Li ◽  
Qingshan Huang ◽  
Shenglin Wang ◽  
Zhen Huang ◽  
Fengqiang Yu ◽  
...  

Abstract Osteosarcoma is the most common primary malignant bone tumor, which occurs in adolescents. As reported by our previous studies, HER4 indicates a poor prognosis of primary osteosarcoma. However, its mechanisms in the pathogenesis of osteosarcoma have not yet been studied. The purpose of this study was to investigate the role of HER4 in osteosarcoma and whether the PI3K/AKT pathway is involved. In this study, western blot analysis was used to investigate the expression of HER4 protein in osteosarcoma tissues and cell lines. CCK8 and transwell assays were used to detect the effects of HER4 on the proliferation, migration, and invasion of osteosarcoma cells in vitro. The effects of HER4 on the growth and metastasis of osteosarcoma in vivo were detected by tumor formation and immunofluorescence in nude mice. The role of the PI3K/AKT pathway in HER4 regulation of the growth and metastasis of osteosarcoma was examined by western blot analysis and immunofluorescence assay. We found that HER4 protein was highly expressed in clinical osteosarcoma specimens and osteosarcoma cells. HER4 markedly promoted the proliferation, migration, and invasion of osteosarcoma cells in vitro as well as the growth and metastasis of osteosarcoma in vivo. HER4 overexpression upregulated the expression of phosphorylated protein kinase B (pAKT), proliferation marker antigen Ki67, and metastasis cell marker matrix metalloproteinase 9 (MMP9). Notably, PI3K/AKT inhibitor LY294002 significantly inhibited the effects of HER4 via the downregulation of pAKT, Ki67, and MMP9. Moreover, LY294002 markedly blocked the effects of HER4-induced upregulation of tumor malignancy. The present study suggests that HER4 may promote the growth and metastasis of osteosarcoma via the PI3K/AKT pathway. The HER4/PI3K/AKT pathway could serve as a potential target for the treatment of osteosarcoma.


2021 ◽  
Vol 2021 ◽  
pp. 1-15
Author(s):  
Brice E. N. Wamba ◽  
Paramita Ghosh ◽  
Armelle T. Mbaveng ◽  
Sayantan Bhattacharya ◽  
Mitra Debarpan ◽  
...  

Piper capense belongs to Piperaceae family and has long been used as a traditional medicine to treat various diseases in several parts of Africa. The present study aims to investigate the effect of Piper capense fruit extract (PCFE) alone and in combination with dacarbazine on metastatic melanoma cell line B16-F10 and in vivo in C57BL/6J mice. Cytotoxic effects of PCFE alone and in association with dacarbazine on B16-F10 cells were studied by 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyl tetrazolium bromide (MTT) assay and colony formation assay. Wound healing assay, immunofluorescence staining, and western blot analysis were performed to evaluate the individual and combined effect of PCFE and dacarbazine on epithelial-mesenchymal transition (EMT). For in vivo studies, C57BL/6J mice were subcutaneously injected with B16-F10 cells (5 × 105 cells/mL), and the effect of PCFE and dacarbazine was studied on tumor development. The alteration of EMT was evaluated by targeting E-cadherin, vimentin, and CD133 in PCFE alone and in combination with dacarbazine-treated tumor tissues by western blot analysis. Phytochemical screening of PCFE reveals the presence of certain secondary metabolites. Our results showed that PCFE alone and in association with dacarbazine has a good activity in preventing B16-F10 melanoma cell progression and clonogenicity. This extract also regulated EMT. In vivo results showed that PCFE (100 mg/kg body weight) reduced tumor size in C57BL/6J mice along with the decrease in the expression of vasculogenic mimicry (VM) tubes as well as an improvement in the qualitative and quantitative expression of markers involved in EMT. Our study suggests that PCFE may be useful for managing the growth and metastasis of melanoma.


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